The piston diameter is different, I want to say 30mm and 34mm. Do your research, you want it to work correctly hydraulically. someone will chime in with the right way to go I'm sure.

 

Yes it's the piston size that's different. Other than that they mount exactly the same.

There is an equation that you need to do where you take the piston size of the master cylinder and get the ratio between the MC and the calipers. According to the maths the M4 should be the better option, but when I was doing all the research and talking to guys who had used both the consensus was that the M50s provides a firmer feel while the M4s have a softer feel - if that's the right way to describe it. Maybe mushier? So it probably depends a bit on how you want your brakes to feel.

You need to have the correct ratios between your master cylinder and your brake calipers based on how much fluid is moved/should move. Not all bikes have an appropriate matching MC/Calipers. So, for example, if we take these three calipers. The M50 (monoblock calipers that come on the Panigale 1199), the M4 (monoblock calipers that came on older 1198s) and the P4 calipers.

M50s have 30mm pistons in the calipers.
P4s have 32mm Pistons in the calipers.
M4s have 34mm pistons.

M50s use a 16mm piston radial Master Cylinder,
MTS' use an 18mm piston radial MC,
M4's are paired with a 19mm radial MC.

So they say, that the ideal ratio of volume from the calipers to the master cylinder is around 27:1 or so.

30:1 - soft feel
27:1 - sweet spot for design
23:1 - firm feel
20:1 - wooden feel

So to figure out what the volume of each is, you have to take the piston size, divide it by two, then multiply it twice by 3.1416 (pie).

So, to figure out what the P4/OEM system is, take the master cylinder at 18, divide that by two. 3.1416 x 9 x 9 = 254 sq. mm.

Then do the same for the each of the pistons on the calipers. So, with the 32mm calipers, 3.1416 x 16 x 16 = 804 sq. mm per piston, but there's 8 pistons. So 804 x 8 = 6434.

Then divide 6434/254 = 25.3:1 - a little on the firm side according to what it is they say, which is accurate from my experience for when the brakes are cold.

So for comparison, M50 has 30mm pistons but comes with a 16mm master cylinder, so the end ratio is 5655/201 = 28:1 (a little on the soft side according to that scale)

The M50s with the MTS' 18mm MC, 5655/254 = 22:1 - according to that chart, the end result should be between firm and wooden. But from what I was told the normal math ratio is a little misleading because even though the M50 has smaller pistons, it holds/moves more fluid.

These individuals I spoke with all felt like the M50s with the MTS MC was their favorite combination. But as with all things YMMV

 

So they say, that the ideal ratio of volume from the calipers to the master cylinder is around 27:1 or so.

30:1 - soft feel
27:1 - sweet spot for design
23:1 - firm feel
20:1 - wooden feel

It's more about "dosing" of the brakes, where above mentioned ratio's apply. And it is a person's preference what they like, as you stated correctly.

Different types of brake pads / discs and it's combination are more responsible for the "feeling" of your brakes.

(Obviously fading excepted, that is another topic.)

 

I had been wondering the same if M50s are worth the extra $.
Canyon~ Thanks for the very informative response. Stuff like that really helps to ubderstand what's going on a try and make informed choices. I tip my hat to you sir. Well done!

 

I made some calculations in a excel sheet.

 

Very helpful all! Using Canyon-chaser's video, I ordered the parts to do a front brake upgrade on mine. I too was wondering about the differences between the M4 vs. M50. Who doesn't want to save a little bit of cash? I personally would like a firmer feel especially when pushing hard during "spirited" riding. I went with the M50's in pursuit of that.

 

I went with the M50's in pursuit of that.

Did you get them fitted? How did the fitting go? What's the result like?

 

The stock set up is kind'a soft and mushy IMHO, so the M50/stock MC might be just about 'purrfec' for me. Thanks!

On a similiar note: how big of a PIA is it bleeding a ABS system? I've bled numerous standard brakes, on my street and track bikes, but never a ABS system.

 

If you have a 2010-2012, then bleeding is the same as anything else. It just takes longer because of the ABS pump.

If you have a 2013-2014, I can't imagine it'll be easy at all because those models have linked brakes, and according to "my guy" Linked brakes with ABS are extremely difficult to bleed because each circuit needs to be bled independently then (interdependently?) as an entire system.

dp

 

Belgium, May I ask which new rear caliper you bought? Surely not another stock one? Thinking about upgrading calipers. If you have part numbers to that would be excellent.

 

Sorry man, I replaced the caliper with a stocker. I'm stock on the rear with the exception of EBC HH pads and the ebrew shield. It's all I've really needed once I got the heat issues sorted out.

The front though is a different matter. EBC V rotors, EBC HH pads, and soon M50 calipers.....

 

Here's my thoughts. Basic hydraulic theory states the larger the area of the(in this case)caliper pistons, the less effort required to operate it. The trade-off is increased lever travel, in other words, you have to be able to actuate it fully using the amount of fluid the master cylinder displaces when squeezed. As long as the master cylinder/lever has enough travel to completely lock wheel, I'd lean toward larger piston area in caliper any time. Easier to one finger it. I would not want a design where it takes 4 finger heft for maximum braking power.

 

M4-V-M50 calipers

Excellent dissertation Canyon-Chaser. Not sure where I saw it mentioned but the Brembo M50 calipers, celebrating 50 years of Brembo making brakes, were 100 grams lighter than the M4 items. Not all the weight in the world but unsprung weight. But who has not changed tire brand or style and not given a second thought to tire weight difference!! I believe the 13-14 Multistrada linked brakes are electronically linked. If you look at the parts manual for these years only 5 brake lines show up. Page 118 of the US parts manual. If hydraulically linked a system failure at either end would possibly allow all the bikes brake fluid to bleed out. Not so good I think.
The 2015 Multistrada will come with M50 front calipers and a 16mm master cylinder.

Cheers

 

I believe the 13-14 Multistrada linked brakes are electronically linked. If you look at the parts manual for these years only 5 brake lines show up. Page 118 of the US parts manual. If hydraulically linked a system failure at either end would possibly allow all the bikes brake fluid to bleed out. Not so good I think.

Cheers

I think you are correct in it being electronically linked. I say this because the first bike I owned with "linked brakes" was a CBR 1100XX. There was a line that physically linked the front to the rear brakes that ran the length of the bike. I also noticed that if I was "covering" the rear brake and got on the front, the rear brake lever would actually depress. I've never felt that with the Multi but on dirt I can feel that they are linked when braking hard with the front and clutch pulled in.

When I replaced my rear caliper it was after a track day. I assumed the mussy brakes was due to replacing the caliper. Probably not now that I think about it...

 

So, swapping 'em out/bleeding the system is just like any other system...meaning no big deal. It appears that the biggest PIA is getting all the body work off (which I've done before) to get to the line and replace it. Gotta love all that body work!

 

If you are anywhere close to a Desmo service, hold off until then. All of the body work has to come off then. It would also be very handy to remove the brake lines to facilitate removal of the vertical cylinder belt cover.

 

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